Siege of Rennes (1356)

The Siege of Rennes was a failed attempt by the Kingdom of England's noble Henry of Grosmont to capture the French castle of Rennes in Brittany during the Breton Civil War. Breton general Bertrand du Guesclin slipped into the castle and took charge of the defenses and valiantly held out against English attacks, and the English were eventually forced to withdraw.